The state of Florida is best known for its beaches and swaying palm trees. But a good chunk of it is swampland. The famous Everglades, a slow-moving sheet of water full of plants and alligators, cover much of the southern part of the state.

To the north, the Okefenokee, which is partly in Florida and mostly in neighboring Georgia, is a true swamp, with its own gators and snakes and even beautiful orchids.

The Okefenokee seems primeval. It was formed when waters from an ancient ocean receded and a mammoth sandbar blocked most of the water flow to the sea. Left behind was an 1,800-square-kilometer swamp.

A watery reflection of a cypress tree that manages to survive despite being submerged.

There's no big city within 200 km, but tourists from all over the world manage to find it. They all want to know about its unusual name. Okefenokee is a Miccosukee Indian word meaning land of trembling earth. Way back in the swamp are small, floating islands, called hammocks, that one can walk across. And they tremble. Standing on them is like trying to balance on a floating mattress.

Don't let this photo of the Okefenokee Swamp fool you. It looks like there's nice, steady ground to walk on, but the surface is spongy at best and submerged in many places.

Water in the Okefenokee is dark, like tea that has steeped a long time. The color comes from tannin that seeps from towering cypress trees draped in Spanish moss.

Every once in awhile, the rangers must crack down on reckless pilots of air boats that skim across the swamp, endangering themselves and others and tearing up delicate foliage. And developers, logging companies, and strip-mine operators on the edge of the swamp can easily upset the delicate balance of nature in the area.

The Okefenokee, which is already nearly choked with plants, would probably fill in, dry up, and become just another cypress and pine forest were it not for range fires that come along every once in awhile and burn out decayed vegetation. So the water in this protected National Wildlife Refuge keeps moving - slowly, very slowly.